WO2007145218A1

WO2007145218A1 - Hydrogen generation device and fuel cell system equipped with it

Info

Publication number: WO2007145218A1
Application number: PCT/JP2007/061831
Authority: WO
Inventors: Kunihiro Ukai; Akira Maenishi; Yuji Mukai; Toru Nakamura; Masaya Tsujimoto; Shingo Nagatomo
Original assignee: Panasonic Corporation
Priority date: 2006-06-12
Filing date: 2007-06-12
Publication date: 2007-12-21
Also published as: US20090317671A1; CN101466635A; CN101466635B; US8273489B2

Abstract

A hydrogen generation device in which not only complication of a steam channel is retrained and durability performance is enhanced but also the possibility of obstruction of reforming reaction or destruction of a reforming catalyst due to nonevaporation liquid water supplied from a steam unit is reduced. The hydrogen generation device (100a), comprising a heater (1) for generating combustion gas by combusting mixture gas of combustion fuel and combustion air, an annular preheating evaporator (6) for generating mixture gas of material and steam by heating the material and steam with the combustion gas generated by the heater, and an annular reformer (2) disposed below the preheating evaporator and generating hydrogen containing gas by passing the mixture gas generated from the preheating evaporator through a reforming catalyst (2a) heated by the combustion gas, is further provided with a water trap section (7) for trapping the liquid water discharged from the preheating evaporator. Furthermore, an annular transforming device (3) incorporating a transforming catalyst (3a) for reducing carbon monoxide in the hydrogen containing gas generated from the reformer by shift reaction is provided on the outer circumference of the preheating evaporator, and heat is exchanged between the hydrogen containing gas supplied from the reformer to the transforming device and the liquid water in the water trap.

Description

Specification

Hydrogen generator and fuel cell system including the same

Technical field

The present invention relates to a hydrogen generator in which a reformer that generates a hydrogen-containing gas, a converter and a selective oxidizer that reduce the concentration of carbon monoxide and carbon, and a heater that heats them are integrated. The present invention relates to a device and a fuel cell system including the same.

Background art

Conventionally, a fuel cell system capable of small-scale high-efficiency power generation has been easy to construct a system for using thermal energy generated during power generation operation, and therefore has high energy utilization efficiency. Development is underway as a distributed power generation system that can be realized.

In a fuel cell system, during a power generation operation, a hydrogen-containing gas containing hydrogen and an oxygen-containing oxygen are contained in a fuel cell stack (hereinafter simply referred to as “fuel cell”) disposed as a main body of the power generation unit. Each of the contained gases is supplied. Then, in the fuel cell, hydrogen contained in the supplied hydrogen-containing gas and oxygen contained in the oxygen-containing gas are used, and a predetermined electrochemical reaction proceeds. As the predetermined electrochemical reaction proceeds, the chemical energy of hydrogen and oxygen is directly converted into electrical energy in the fuel cell. As a result, the fuel cell system outputs power toward the load.

[0004] Now, the means for supplying the hydrogen-containing gas required during the power generation operation of the fuel cell system is not usually provided as an infrastructure. Therefore, in conventional fuel cell systems, for example, a temperature of 600 ° C to 700 ° C using city gas or LPG or other raw material gas that can also provide existing fossil raw material infrastructure power and water vapor generated by a water evaporator. In many cases, a reformer that proceeds with a steam reforming reaction to generate a hydrogen-containing gas is provided together with the fuel cell. On the other hand, the hydrogen-containing gas obtained by the steam reforming reaction usually contains a large amount of carbon monoxide and carbon dioxide derived from the raw material gas. Therefore, in the conventional fuel cell system, the temperature of the hydrogen-containing gas is reduced to 200 ° C in order to reduce the concentration of acid-carbon in the hydrogen-containing gas produced by the reformer. By a water gas shift reaction at a temperature of ˜350 ° C. to reduce the concentration of carbon monoxide and carbon, and a selective oxidation reaction at a temperature of 100 ° C. to 150 ° C. In many cases, a selective oxidizer that further reduces the concentration of carbon monoxide is provided together with a fuel cell reformer. Here, in the conventional fuel cell system, the hydrogen generator is constituted by these reformer, transformer, and selective oxidizer. Each of these reformer, shifter and selective oxidizer is provided with a catalyst suitable for each chemical reaction for proceeding with each of the steam reforming reaction, water gas shift reaction and selective oxidation reaction. ing. For example, the reformer is provided with Ru catalyst or Ni catalyst. The transformer is provided with a Cu-Zn catalyst and a noble metal catalyst. The selective oxidizer is provided with a Ru catalyst or the like.

[0005] By the way, in the hydrogen generator having the above-described configuration, it is generally necessary to maintain the temperature of each reactor at an optimum temperature in order to appropriately advance the chemical reaction in each reactor. In addition, in the hydrogen generator having the above-described configuration, it is an important issue to effectively use the thermal energy necessary for maintaining the temperature of each reactor at an optimum temperature.

[0006] In view of this, there has been proposed a hydrogen generator in which each of a reformer, a water evaporator, a transformer, and a selective oxidizer is arranged concentrically around a heater (for example, Patent Document 1). reference).

[0007] On the other hand, in the case of the configuration of the hydrogen generator as described in Patent Document 1, normally, when steam generated by a water evaporator disposed on the outer peripheral side of the reformer is supplied to the reformer. In addition, the structure of the water vapor flow path is complicated by changing the flow of the water vapor delivered from the water evaporator force from the axial direction of the water evaporator to the circumferential direction. As a result, for example, the mixed gas supply pipe connecting the steam flow path and the reformer inlet extends in the radial direction, and welding or the like is performed at the connection point between the mixed gas supply pipe and the reformer extending in the axial direction. It is necessary to install the piping. This piping for the water vapor channel may increase the cost of the hydrogen generator and deteriorate the durability.

[0008] In view of this, there has been proposed a hydrogen generator in which a cylindrical water evaporator and a reformer are arranged side by side in the same axial direction (see, for example, Patent Document 2).

Patent Document 1: JP 2002-187705 A

Patent Document 2: Japanese Patent Laid-Open No. 2005-225684 Disclosure of the invention

Problems to be solved by the invention

[0009] Here, in order to eliminate the problem of the cost increase of the hydrogen generator and the deterioration of the durability performance due to the complicated configuration of the water vapor channel, the hydrogen generator described in Patent Document 1 is As described in Patent Document 2, it is assumed to incorporate a configuration in which a cylindrical water evaporator and a reformer are arranged side by side in the same axial direction.

[0010] However, in this case, since the water evaporator is disposed above the reformer, liquid water that has not evaporated in the water evaporator is directly supplied to the reforming catalyst in the reformer. There is a possibility that. In this case, if the reforming catalyst is locally cooled, inhibition of the reforming reaction may cause bowing of the reforming catalyst.

[0011] The present invention has been made to solve the above-described problems of the conventional hydrogen generator and the fuel cell system including the conventional hydrogen generator, and suppresses complication of the water vapor channel and improves durability. The present invention provides a hydrogen generator and a fuel cell system equipped with the hydrogen generator that reduce the possibility that the reforming reaction will be inhibited by the non-evaporated liquid water that is supplied by the power of the water evaporator. The purpose is that.

Means for solving the problem

[0012] In order to solve the above problems, a hydrogen generator according to the present invention includes a heater that generates a combustion gas by burning a mixture of combustion fuel and combustion air, and the heater generates A ring-shaped preheating evaporator in which the raw material and water are heated by the combustion gas to generate a mixture of the raw material and water vapor, and the mixed gas generated by the preheating evaporator below the preheating evaporator. And an annular reformer that generates a hydrogen-containing gas by passing the gas through a reforming catalyst heated by the combustion gas, and further includes a water trap section that traps liquid water discharged from the preheating evaporator. I have.

[0013] With a powerful configuration, since the liquid water from which the preheat evaporator power has been discharged is trapped by the water trap unit, the liquid water is directly supplied to the reforming catalyst filled in the reformer, and the reforming catalyst is locally supplied. Therefore, it is possible to reduce the possibility of inhibition of the reforming reaction and destruction of the catalyst caused by rapid cooling.

[0014] In this case, the hydrogen-containing gas generated by the reformer on the outer periphery of the preheat evaporator Further comprising a shifter having a shift catalyst for reducing carbon monoxide therein by a shift reaction, and heat exchange between the hydrogen-containing gas supplied from the reformer to the shifter and liquid water in the water trap section. It is configured to

[0015] With a powerful configuration, heat exchange is performed between the liquid water in the water trap section and the hydrogen-containing gas supplied to the transformer, and the temperature of the hydrogen-containing gas supplied to the transformer by this heat exchange. Can be suitably reduced.

[0016] In this case, the preheat evaporator, the water trap, the reformer, and the transformer are each provided in a cylindrical shape outside the heater, and the transformer is included in the preheat evaporator. The preheat evaporator, the water trap part, and the reformer are supplied from the preheat evaporator to the reformer via the water trap part. The hydrogen-containing gas generated in the reformer is configured to come into contact with the water trap portion before being supplied to the transformer.

[0017] With a powerful configuration, heat exchange is performed between the liquid water in the water trap section and the hydrogen-containing gas supplied to the transformer, and the temperature of the hydrogen-containing gas supplied to the transformer by this heat exchange. Can be suitably reduced.

[0018] In this case, the raw material supply port and the water supply port are provided on the other end side without the water trap portion of the preheating evaporator being connected.

[0019] With such a configuration, since the raw material supply port and the water supply port are provided on the other end side where the heat exchanger of the preheating evaporator is not connected, the mixture of the raw material and water vapor in the preheating evaporator is provided. When the hydrogen generator is installed so that the flow direction and the gravity direction are substantially the same and the reformer is disposed below the gravity direction, the raw material and water vapor generated above the gravity direction of the preheating evaporator This makes it possible to efficiently supply the reformer below the gravitational direction without stagnating the air-fuel mixture.

[0020] In the above case, the hydrogen generator includes a combustion air supply for supplying the combustion air to the heater, a water supply for supplying the water to the preheating evaporator, and the transformer. A temperature detector that detects the temperature of the shift catalyst to be stored, and a controller, and the controller controls the preheat evaporation from the water supply based on the temperature of the shift catalyst detected by the temperature detector. The amount of water supplied to the heater and the heater from the combustion air supply Controlling at least one of the combustion air supply amounts to.

[0021] With such a configuration, the controller heats the amount of water supplied to the preheating evaporator and the combustion air supply from the power of the water supply based on the temperature of the shift catalyst detected by the temperature detector. The temperature of the preheating evaporator changes by controlling at least one of the combustion air supply to the generator, and the temperature of the transformer provided on the outer periphery of the preheating evaporator can be controlled accordingly. .

[0022] In this case, the hydrogen generator includes a storage device having information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst, and the controller has a temperature detected by the temperature detector equal to or higher than the upper limit temperature. If the temperature of the preheat evaporator becomes less than the lower limit temperature, the water supplier is controlled to increase the amount of water supplied to the preheat evaporator. The water supply is controlled so as to reduce the amount of water supplied to the water.

[0023] With a powerful configuration, by controlling the amount of water supplied to the water supply power preheating evaporator, the temperature of the preheating evaporator changes or the amount of liquid water in the water trap section fluctuates. This leads to fluctuations in the amount of heat transferred from the transformer to the preheating evaporator, or the amount of heat exchange between the hydrogen-containing gas supplied to the converter and the water trap, making it possible to control the temperature of the conversion catalyst.

[0024] In this case, the storage device further includes information on an upper limit supply amount and a lower limit supply amount relating to the control of the water supply amount, and the controller supplies water from the water supply device to the preheating evaporator. It is determined that there is an abnormality when the amount exceeds the upper limit supply amount or when the water supply amount from the water supplier to the preheat evaporator becomes equal to or less than the lower limit supply amount.

[0025] If the configuration is powerful, the controller determines that an abnormality occurs when the water supply amount to the water supply power preheat evaporator exceeds the upper limit supply amount or below the lower limit supply amount. The user can detect the occurrence of an abnormality.

[0026] In the above case, the hydrogen generator includes a storage device having information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst, and the controller detects the detected temperature of the temperature detector. When the temperature exceeds the upper limit temperature, the combustion air supply device is controlled to reduce the amount of combustion air supplied to the heater, and the temperature detected by the temperature detector is equal to or lower than the lower limit temperature. In this case, increase the amount of combustion air supplied to the heater. Control the combustion air supply.

[0027] With a powerful configuration, the amount of heat transferred to the combustion gas power preheating evaporator varies by controlling the amount of combustion air supplied to the combustion air supply power heater, so the temperature of the preheating evaporator Changes. This leads to fluctuations in the amount of heat transferred from the converter to the preheating evaporator, and it becomes possible to control the temperature of the conversion catalyst.

[0028] In this case, the storage device further includes information on an upper limit supply amount and a lower limit supply amount related to the control of the combustion air supply amount, and the controller is connected to the heater from the combustion air supply device. It is determined that there is an abnormality when the combustion air supply amount to the upper limit supply amount is greater than or equal to the upper limit supply amount or the combustion air supply force is less than the lower limit supply amount. To do.

[0029] With this configuration, the controller determines that there is an abnormality when the amount of combustion air supplied from the combustion air supply to the heater exceeds the upper limit supply amount or less than the lower limit supply amount. Therefore, it becomes possible for an operator or a user to detect the occurrence of an abnormality.

[0030] Further, in the above case, the hydrogen generation device includes information on the upper limit temperature and the lower limit temperature related to the temperature control of the shift catalyst and information on the upper limit supply amount and the lower limit supply amount related to the control of the water supply amount. And when the temperature of the shift catalyst is equal to or higher than the upper limit temperature, and the water supply force is less than or equal to the upper limit supply amount. Controls the combustion air supply so as to reduce the amount of combustion air supplied to the heater, the temperature of the shift catalyst is lower than the lower limit temperature, and water from the water supply to the preheating evaporator When the supply amount becomes equal to or less than the lower limit supply amount, the combustion air supply device is controlled so as to increase the combustion air supply amount to the heater.

[0031] Alternatively, in the above case, the hydrogen generation device may include information on the upper limit temperature and the lower limit temperature related to the temperature control of the shift catalyst and the upper limit supply amount and the lower limit supply amount related to the control of the combustion air supply amount. And the controller has a temperature of the shift catalyst equal to or higher than the upper limit temperature, and a combustion air supply amount from the combustion air supply device to the heater is equal to or lower than the lower limit supply amount. In this case, the water supplier is controlled to increase the amount of water supplied to the preheating evaporator, and the temperature of the shift catalyst is set to the lower limit temperature. The water supply unit is configured to reduce the water supply amount to the preheating evaporator when the combustion air supply amount from the combustion air supply unit to the heater is equal to or greater than the upper limit supply amount. To control.

[0032] With a powerful configuration, the transformer is built in by both the water supply force control of the water supply amount to the preheating evaporator and the control of the combustion air supply amount from the combustion air supply device to the heater. Since the temperature of the shift catalyst is controlled, the temperature control of the shift catalyst can be more reliably performed during operation of the fuel cell system.

[0033] On the other hand, the fuel cell system according to the present invention generates power using the characteristic hydrogen generation apparatus according to the present invention, and the hydrogen-containing gas and the oxygen-containing gas supplied from the hydrogen generation apparatus. And at least a fuel cell.

[0034] With a powerful configuration, the fuel cell system uses the characteristic hydrogen generator according to the present invention and a fuel cell that generates power using the hydrogen-containing gas and the oxygen-containing gas supplied by the hydrogen generator. Therefore, liquid water is directly supplied to the reforming catalyst filled in the reformer and the reforming catalyst is inhibited by local quenching, which may inhibit the reforming reaction and destroy the catalyst. Performance is reduced, and a hydrogen-containing gas having a stable composition is supplied. This makes it possible to provide a fuel cell system that can continue stable operation.

The invention's effect

[0035] According to the hydrogen generator of the present invention, the liquid water from the preheat evaporator is trapped by the water trap unit, so that the liquid water is directly supplied to the reforming catalyst filled in the reformer, and the reforming is performed. Stable hydrogen production is possible because the possibility of inhibition of the reforming reaction and destruction of the catalyst caused by local quenching of the catalyst is reduced.

[0036] Further, according to the fuel cell system including the hydrogen generator according to the present invention, the hydrogen generator operates stably, and a high-quality hydrogen-containing gas having a stable composition is stabilized toward the fuel cell. It is possible to provide a fuel cell system capable of stable power generation operation.

Brief Description of Drawings

FIG. 1 is a block diagram and a cross-sectional view schematically showing a first configuration of a hydrogen generator according to Embodiment 1 of the present invention and an additional configuration for driving the first configuration. is there. FIG. 2 is a block diagram and a cross-sectional view schematically showing a second configuration of the hydrogen generator according to Embodiment 1 of the present invention and an additional configuration for driving the second configuration.

FIG. 3 is a schematic diagram for explaining the principle of the present invention.

FIG. 4 is a flowchart schematically showing one cycle of characteristic operations of the hydrogen generator according to Embodiment 1 of the present invention.

FIG. 5 is a flowchart schematically showing one cycle of characteristic operations of the hydrogen generator according to Embodiment 2 of the present invention.

[FIG. 6] FIG. 6 is a graph schematically showing the results of one evaluation example regarding the temperature activity of a Cu—Zn-based shift catalyst.

Explanation of symbols

1 Heating part

2 Modification section

2a Reforming catalyst

2b Temperature detector

3 Metamorphosis Department

3a shift catalyst

3b, 3c Temperature detector

4 Selective oxidation part

4a Selective oxidation catalyst

4b Temperature detector

5 Combustion gas flow path

6 Preheating evaporator

6a stick

7 Water trap

8 Heat exchanger

9 Water supply

10 Raw material feeder

11 Combustion air supply 12 Air supply for selective oxidation

13a, 13b Channel switching valve

14 Controller

a Upper wall

b Lower wall

A Exterior wall

B Inner wall

B1 First inner wall

B2 Second inner wall

B3 Third inner wall

C Bulkhead

C1 First bulkhead

C2 Second partition

C3 Third bulkhead

C4 Fourth bulkhead

P1 evaporation section

P2 heat exchanger

100a, 100b hydrogen generator

101 Water supply port

102 Raw material supply port

103 Air supply port

104 gap

105 Fuel gas outlet

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

[0040] (Embodiment 1)

First, the basic configuration of the hydrogen generator according to Embodiment 1 of the present invention will be described. To do.

FIG. 1 is a block diagram and a cross-sectional view schematically showing a first configuration of the hydrogen generator according to Embodiment 1 of the present invention and an additional configuration for driving the first configuration.

[0042] As shown in FIG. 1, the hydrogen generator 100a according to the present embodiment supplies a gas source gas such as city gas or LPG obtained from the existing fossil raw material infrastructure, or a fuel cell. A cylindrical heating part 1 for heating a reforming part 2, a transformation part 3 and a selective oxidation part 4 to be described later by burning a hydrogen-containing gas containing carbon monoxide and carbon dioxide exceeding a predetermined concentration, The heating unit 1 is provided with a reforming unit 2, a transformation unit 3, and a selective oxidation unit 4 that are concentrically and integrally disposed with the heating unit 1.

Specifically, as shown in FIG. 1, the hydrogen generator 100a has a predetermined diameter, and an upper opening and a lower opening are an upper wall portion a and a lower wall portion b. Concentric with the outer wall A so that its upper and lower ends are connected to the cylindrical outer wall A closed by the upper wall a and lower wall b disposed above and below the outer wall A. And a substantially cylindrical inner wall portion B having a diameter smaller than the diameter of the outer wall portion A provided therein.

[0044] Here, the inner wall portion B has a cylindrical first inner wall portion B1 extending vertically from the upper wall portion a to a predetermined position, and a lower end of the first inner wall portion B1. A ring-shaped second inner wall B2 to which the outer edge is connected, and a cylinder having an upper end connected to the inner edge of the second inner wall B2 and extending vertically downward to the lower wall b And a third inner wall B3

Further, as shown in FIG. 1, the hydrogen generator 100a includes a substantially cylindrical partition wall C between the outer wall A and the inner wall B.

[0046] Here, the upper end of the partition wall C is connected to the upper part of the outer wall A spaced a predetermined distance from the upper wall a, and the partition C is inclined downward at a predetermined angle from the connection. The first conical first partition wall C 1 extending to a predetermined position in the vicinity of the inner wall B and the bottom end force of the first partition wall C 1 is a cylinder extending vertically to the predetermined position. And a second partition wall portion C2.

[0047] Then, above the cylindrical region surrounded by the inner wall portion B, the central axis and the central axis of the hydrogen generator 100a are aligned, and between the wall portion and the first inner wall portion B1. Combustion gas flow A cylindrical heating section 1 for heating the reforming catalyst 2a of the reforming section 2 through the third inner wall section B3 is provided so as to form the path 5. This heating unit 1 is provided with a combustion burner (not shown in FIG. 1), and is supplied from a raw material supplier 10 (to be described later) using combustion air supplied from a combustion air supplier 11 (to be described later) having a sirocco fan or the like. Combustion of hydrogen-containing gas containing a certain concentration or more of carbon monoxide that cannot be supplied to the fuel cell supplied through the flow path switching valves 13a and 13b described later. As a result, the temperature of the reforming catalyst 2a in the reforming section 2 is heated to a temperature suitable for the progress of the steam reforming reaction and kept warm. Here, in this embodiment, in order to improve the thermal efficiency in generating the hydrogen-containing gas, the combustion gas discharged from the heating unit 1 burns after the reforming catalyst 2a of the reforming unit 2 is heated. A configuration is also employed in which the preheating evaporation section 6 described later passes through the gas flow path 5 and is also heated. The combustion gas discharged from the heating unit 1 and used to heat the reforming catalyst 2a and the preheating evaporation unit 6 of the reforming unit 2 is also an exhaust gas exhausting loca provided at the upper part of the hydrogen generator 100a. It is discharged outside the hydrogen generator 100a as exhaust gas.

Further, as shown in FIG. 1, the hydrogen generator 100a includes a cylindrical reforming catalyst 2a between a predetermined lower portion of the third inner wall portion B3 and the second partition wall portion C2. It has. In the present embodiment, the reforming catalyst 2a is composed of a Ru-based catalyst, and a raw material such as city gas, a hydrocarbon-based component such as LPG, an alcohol such as methanol, or a naphtha component, or a raw material gas and steam. The steam reforming reaction to be used mainly proceeds to generate a hydrogen-containing gas containing hydrogen as a main component and carbon monoxide as a subcomponent. Here, the reforming unit 2 according to the present embodiment indirectly detects the temperature of the reforming catalyst 2a by detecting the temperature of the reforming catalyst 2a and the hydrogen-containing gas discharged from the reforming catalyst 2a. Temperature detecting section 2b.

In addition, as shown in FIG. 1, in this hydrogen generator 100a, a cylindrical shift catalyst 3a and a selection catalyst are selected between a predetermined upper portion of the outer wall portion A and the second partition wall portion C2. An oxidation catalyst 4a is provided. Here, the shift catalyst 3a is a predetermined position on the side close to the reforming catalyst 2a (i.e., the flow of the hydrogen-containing gas) in the cylindrical region surrounded by the predetermined portion of the outer wall portion A and the second partition wall portion C2. On the upstream side). On the other hand, selective oxidation catalyst 4a is disposed at a predetermined position far from the reforming catalyst 2a in the cylindrical region (that is, downstream of the flow of the hydrogen-containing gas). The shift catalyst 3a and the selective oxidation catalyst 4a are disposed so as to be separated from each other by a predetermined distance. An air supply port 103 is provided so as to communicate with the space between the shift catalyst 3a and the selective oxidation catalyst 4a. Also, a fuel gas outlet 105 is provided in the outer wall portion A so as to communicate with the space above the selective acid catalyst 4a.

[0050] In this embodiment, the shift catalyst 3a is composed of a Cu-Zn-based catalyst, and steam is used as the concentration of carbon monoxide contained in the hydrogen-containing gas generated in the reforming section 2. By proceeding mainly with the water gas shift reaction, the concentration is reduced below a predetermined concentration. Here, the shift unit 3 according to the present embodiment detects the temperature of the shift catalyst 3a and the temperature of the shift catalyst 3a indirectly by detecting the temperature of the hydrogen-containing gas introduced into the shift catalyst 3a. And a temperature detector 3c that directly detects the temperature of the shift catalyst 3a. On the other hand, the selective oxidation catalyst 4a is composed of a Ru-based catalyst in the present embodiment, and the concentration of monoxide carbon that is still contained in the hydrogen-containing gas in which the concentration of monoxide carbon is reduced in the shift section 3 This is further reduced to a predetermined concentration or less by mainly proceeding with a selective oxidation reaction using air supplied from the air supply port 103 by the selective oxidation air supplier 12 described later. The hydrogen-containing gas that has passed through the selective oxidation catalyst 4a is taken out from the fuel gas outlet 105. Here, the selective oxidation unit 4 according to the present embodiment includes a selective oxidation catalyst 4a and a temperature detection unit 4b that directly detects the temperature of the selective oxidation catalyst 4a.

[0051] Next, the configuration of the preheating evaporation unit and the heat exchange unit in the hydrogen generator according to Embodiment 1 of the present invention will be described.

[0052] In the hydrogen generator 100a according to the present embodiment, the first and second partition walls CI, C2 in the upper part of the outer wall part A, the end part of the upper wall part a, the upper part of the inner wall part B, and the partition part C. A preheating evaporation section 6 for evaporating water supplied from a water supply device 9 to be described later is configured over a predetermined region surrounded by the above. The preheating evaporation section 6 includes an evaporation rod 6a in a cylindrical area between the first inner wall section B1 of the inner wall section B and a predetermined portion of the second partition wall section C2 facing the first inner wall section B1. Is arranged. In the present embodiment, the evaporation rod 6a is formed in the vertical direction in which the second partition wall C2 in the partition wall C is directed from the upper end to the lower end. A cylindrical region between the wall portion B and the second partition wall portion C2 extends so as to swirl around the heating portion 1 in a spiral manner. Further, the evaporation rod 6a is disposed so that the outer peripheral portion thereof is in contact with the inner wall portion B and the second partition wall portion C2. The upper wall portion a is provided with a water supply port 101 so as to communicate with the preheating evaporation unit 6. That is, in the present embodiment, the preheating evaporation unit 6 is configured such that the water supplied from the water supplier 9 through the water supply port 101 flows along the first partition wall portion C1 in the partition wall portion C, and then the evaporation rod It is configured so as to flow down while spirally turning between the inner wall portion B and the second partition wall portion C2 vertically downward along 6a. In addition, the preheating evaporation section 6 is provided with a raw material supply port 102 communicating with the preheating evaporation section 6 on the outer wall portion A, and the raw material gas supplied from the raw material supply device 10 to be described later through the raw material supply port 102 is supplied. Supplied to the space above the first partition wall portion C1 in the partition wall portion C, and then spirally swivels between the inner wall portion B and the second partition wall portion C2 with the space above the evaporation rod 6a directed vertically downward. It is configured to move. The raw gas supplied from the raw material supplier 10 by the preheating evaporation unit 6 is heated to a predetermined temperature by the high-temperature combustion gas discharged from the heating unit 1 and the water supplied from the water supplier 9 is heated. It is thoroughly mixed with water vapor obtained by evaporating water. As a result, a mixture of the raw material gas and the water vapor is generated in the preheating evaporator 6. The mixture of the raw material gas and water vapor is then supplied to the reforming catalyst 2a in the reforming section 2.

Further, as shown in FIG. 1, in the hydrogen generator 100a according to the present embodiment, a part of the second partition wall part C2 in the partition wall part and a part of the second partition wall part C2 are disposed inside. A heat exchanging portion 8 is constituted by a concave water trap portion 7 provided in an annular shape over the entire circumference. This heat exchanging unit 8 transfers the heat held by the hydrogen-containing gas before being discharged from the reforming unit 2 and supplied to the transformation unit 3 from the transformation unit 3 side through the second partition unit C2. It is configured to move to the 6 side by heat exchange. Here, the water trap section 7 is configured to flow spirally along the evaporation rod 6a of the preheating evaporation section 6 and trap the liquid water discharged without being completely evaporated in the preheating evaporation section 6. . Further, the second partition wall portion C 2 in the partition wall portion C mediates heat transfer between the liquid water stored in the water trap section 7 and the hydrogen-containing gas before being introduced into the shift section 3. Note that the mixture of the raw material gas and water vapor generated in the preheating evaporation section 6 extends over the entire circumference between the heat exchange section 8 and the inner wall section B without staying in the heat exchange section 8. It passes through the formed predetermined gap 104 and is sequentially supplied to the reforming catalyst 2a in the reforming section 2.

As described above, in the present embodiment, in the hydrogen generator 100a, the heating unit 1 is disposed at the center thereof, and the cylindrical preheating evaporation unit 6 is disposed above the heating unit 1 in the gravity direction. A cylindrical heat exchanging portion 8 and a reforming portion 2 are disposed on the lower side in the gravity direction. Here, in order to heat the preheating evaporation unit 6 after heating the reforming catalyst 2a of the reforming unit 2, the combustion gas discharged from the heating unit 1 is passed between the heating unit 1 and the preheating evaporation unit 6. A combustion gas flow path 5 is provided for flow. In the present embodiment, the heat exchanging section 8 is arranged at the boundary between the flow path through which the mixture of the raw material gas and water vapor flows and the flow path through which the hydrogen-containing gas supplied to the shift section 3 flows. The temperature of the hydrogen-containing gas before being supplied to the shift section 3 can be appropriately controlled via the second partition wall section C2. Further, in the present embodiment, the conversion unit 3 and the selective oxidation unit 4 that reduce the concentration of carbon monoxide contained in the hydrogen-containing gas generated in the reforming unit 2 are placed outside the preheating evaporation unit 6. It is arranged so that the heat energy surplus in the transformation unit 3 and the selective acid unit 4 can be supplied to the preheating evaporation unit 6.

[0055] In the present embodiment, since the liquid water from the preheat evaporator 6 is reliably trapped by the water trap section 7 provided in the heat exchanger 8, the reforming catalyst filled in the reforming section 2 is used. It is possible to prevent the reforming catalyst 2a from being destroyed by inhibiting the reforming reaction caused by supplying liquid water directly to 2a and locally cooling the reforming catalyst 2a.

On the other hand, FIG. 2 is a block diagram and a cross-sectional view schematically showing a second configuration of the hydrogen generator according to Embodiment 1 of the present invention and an additional configuration for driving the second configuration. .

As shown in FIG. 2, in the hydrogen generator 100b according to the present embodiment, the configuration of the heat exchange unit 8 and its surroundings is slightly different from the configuration of the hydrogen generator 100a.

More specifically, the hydrogen generator 100b according to the present embodiment is similar to the hydrogen generator 100a in that it has a cylindrical outer wall portion A and upper and lower portions disposed above and below the outer wall portion A. A cylindrical inner wall B having a diameter smaller than the diameter of the outer wall A concentrically provided with the outer wall A so that the upper and lower ends thereof are connected to the wall a and the lower wall b. RU The hydrogen generator 100b includes a substantially cylindrical partition wall C between the outer wall A and the inner wall B as in the hydrogen generator 100a. [0059] Here, the partition wall portion C has a connecting portion force with the outer wall portion A. The first partition wall portion C1 having an inverted conical shape that inclines downward at a predetermined angle and extends to a predetermined position in the vicinity of the inner wall portion B. The lower end force of the first partition wall portion C1 is a cylindrical second partition wall portion C 2 that extends vertically downward to a predetermined position, and the inner edge portion is formed at the lower end of the second partition wall portion C2. Connected ring-shaped third partition wall C3 and a cylinder whose upper end is connected to the outer edge of the third partition wall C3 and extends vertically downward to a predetermined position near the lower wall b And a fourth partition wall portion C4.

[0060] As shown in FIG. 2, in the hydrogen generator 100b according to the present embodiment, a part of the fourth partition wall part C4 in the partition wall part C and a part of the fourth partition wall part C4. A heat exchanging portion 8 is constituted by a concave water trap portion 7 provided in an annular shape over the entire circumference of the inner wall portion B on the inner side. In other words, in the hydrogen generator 100b according to the present embodiment, a flow path through which a mixture of the raw material gas and water vapor flows is provided inside the fourth partition wall C4 in the partition wall, and the inside thereof is provided. Further, a configuration in which the water trap part 7 is arranged is adopted. Here, as in the case of the hydrogen generator 100a, the water trap section 7 of the hydrogen generator 100b flows spirally along the evaporation rod 6a of the preheat evaporator 6 and does not evaporate completely in the preheat evaporator 6. It is configured to trap the discharged liquid water. Even in such a configuration, as in the case of using the hydrogen generator 100a shown in FIG. 1, the temperature of the hydrogen-containing gas before being supplied to the shift unit 3 can be appropriately controlled via the fourth partition wall C4. It becomes possible. In other respects, the configuration of the hydrogen generator 100b and the configuration of the hydrogen generator 100a are the same.

[0061] Next, an additional configuration for driving the hydrogen generator according to Embodiment 1 of the present invention will be described. In the following description, an additional configuration for driving the hydrogen generator 100a will be described for convenience.

As shown in FIG. 1, in the fuel cell system according to the present embodiment, in order to drive the hydrogen generator 100a during the power generation operation, water vapor is supplied to the preheating evaporator 6 of the hydrogen generator 100a. A water supply 9 for supplying water necessary for the progress of the reforming reaction and the city gas or the gas required for the steam reforming reaction to proceed to the heating unit 1 and the preheating evaporation unit 6 of the hydrogen generator 100a. Combustion air required for combustion of city gas, etc. in the combustion burner in the raw material supply device 10 for supplying raw material gas such as LPG and the heating unit 1 of the hydrogen generator 100a And a selective oxidation air supply 12 for supplying selective oxidation air necessary for advancing the selective oxidation reaction to the selective oxidation unit 4 of the hydrogen generator 100a. Each has.

[0063] The water supplier 9 is connected to, for example, an infrastructure that can constantly supply water such as water. Then, after removing foreign substances as necessary, the water supply unit 9 generates hydrogen by appropriately controlling the supply amount of water supplied by water, etc., while appropriately controlling the supply amount of water. The water is supplied to the preheating evaporator 6 in the apparatus 100a through the water supply port 101.

[0064] In the present embodiment, the raw material supplier 10 is connected to the city gas infrastructure. The raw material supplier 10 removes sulfur and other components harmful to the fuel cell system contained in the city gas as needed, and then properly supplies the city gas from which the sulfur etc. has been removed. In addition, the city gas whose supply amount is appropriately controlled is supplied to the preheating evaporation unit 6 in the hydrogen generator 100a through the raw material supply port 102 and also to the heating unit 1.

[0065] The combustion air supply 11 includes a sirocco fan, for example, and removes dust, foreign matter, and the like as necessary with a filter or the like, and then air is supplied to the hydrogen generator 100a with an appropriate supply amount. Supply to heating unit 1.

[0066] Further, the selective oxidation air supply 12 includes, for example, a diaphragm type pump or the like, and after removing dust or foreign matter as necessary with a filter or the like in the same manner as the combustion air supply 11, Air is supplied through the air supply port 103 to the selective acid tank 4 in the hydrogen generator 100a with an appropriate supply amount.

Further, as shown in FIG. 1, the fuel cell system according to the present embodiment includes flow path switching valves 13a and 13b. Here, the flow path switching valve 13a is constituted by, for example, a three-way valve, and switches the flow path through which the hydrogen-containing gas generated by the hydrogen generation apparatus 100a flows. In the present embodiment, the flow path switching valve 13a switches the supply destination of the hydrogen-containing gas generated by the hydrogen generator 100a between the fuel cell and the heating unit 1. Further, the flow path switching valve 13b is configured by, for example, a three-way valve in the same manner as the flow path switching valve 13a, and supplies the raw material gas as the supply source of the combustion gas to the heating unit 1 in the hydrogen generator 100a. It switches between the raw material supply device 10 and the hydrogen production | generation apparatus 100a which supplies hydrogen containing gas.

Further, as shown in FIG. 1, the fuel cell system according to the present embodiment includes a controller 14. The controller 14 is composed of an arithmetic unit such as a microcomputer, and includes an arithmetic unit (not shown in FIG. 1) that also has CPU power, a storage unit (not shown in FIG. 1) that has internal memory power, and the like. Have. Then, the controller 14 is based on the output signals of the temperature detection units 2b, 3b, 3c, 4b, etc. shown in FIG. 1 and the sequence stored in the storage unit during the power generation operation of the fuel cell system. Control the operation of each component of the fuel cell system such as water supply 9, raw material supply 10, combustion air supply 11, selective oxidation air supply 12, flow path switching valves 13a and 13b, etc. To do.

[0069] Next, the principle of the present invention, which is the basis of the characteristic operation of the hydrogen generator according to the present embodiment described below, will be schematically described.

FIG. 3 is a schematic diagram for explaining the principle of the present invention. In the following description, for convenience, it is assumed that the supply amount S1 is the supply amount S2, and the heat amount Hl is less than the heat amount H2. The following explanation is based on a virtual model! Now, the principle of the present invention will be schematically described.

[0071] As shown in FIG. 3 (a), water is supplied at an amount of supply S1 to the evaporation section P1 corresponding to the preheating evaporation section 6 shown in FIG. 1, and at an amount of heat HI to the evaporation section P1. When the heat energy is supplied, the water trap part of the heat exchange part P2 corresponding to the heat exchange part 8 shown in FIG. 1 completely evaporates from the evaporation stick corresponding to the evaporation stick 6a shown in FIG. 1 of the evaporation part P1. The discharged liquid water is trapped. The hydrogen-containing gas that passes in the vicinity of the heat exchange part P2 is adjusted to the temperature T1 by the heat exchange action of the heat exchange part P2 according to the amount of water trapped in the water trap part.

[0072] Now, as shown in FIG. 3 (b), water is supplied to the evaporation section P1 at a supply amount S2 larger than the supply amount S1, and to the evaporation section P1, the water is supplied as shown in FIG. When heat energy is supplied with the same amount of heat H 1 as in the case of), a relatively large amount of liquid water that does not evaporate as the evaporation rod force of the evaporation part P1 is discharged, and the heat exchange part The water trap part of P2 stores water of volume V2, which is larger than volume VI. In this case, since the water is further cooled by the volume V2 of water stored in the heat exchanging part P2, the hydrogen-containing gas passing near the heat exchanging part P2 is adjusted to a temperature T2 lower than the temperature T1. The In other words, the amount of heat energy supplied to the evaporator P1 If not changed, the temperature of the hydrogen-containing gas in contact with the heat exchanger P2 can be arbitrarily controlled by controlling the amount of water supplied to the evaporator PI.

On the other hand, as shown in FIG. 3 (c), when water is supplied to the evaporation part P1 with the supply amount S2, and heat energy is supplied to the evaporation part P1 with the heat quantity HI. In addition, it is assumed that the liquid water that does not evaporate the evaporation rod force of the evaporation part P1 is discharged to the water trap part of the heat exchange part P2, and water of volume V2 is stored. In this case, it is assumed that the hydrogen-containing gas passing through the vicinity of the heat exchange part P2 is adjusted to the temperature T2 by the heat exchange action of the heat exchange part P2.

[0074] Now, as shown in Fig. 3 (d), water is supplied to the evaporation part P1 with the supply amount S2, and the heat energy with the heat quantity H2 greater than the heat quantity HI is supplied to the evaporation part P1. When water is supplied, the amount of liquid water discharged without the evaporation rod force of the evaporation part P1 decreases, and the water trap part of the heat exchange part P2 has a volume VI of less than volume V2. Is stored. In this case, the water-containing gas passing through the vicinity of the heat exchanging part P2 is adjusted to a temperature T1 higher than the temperature T2 because it is weakly cooled by the water of the volume VI stored in the heat exchanging part P2. . In other words, when the amount of water supplied to the evaporator P1 is not changed, the temperature of the hydrogen-containing gas can be arbitrarily controlled by controlling the amount of heat supplied to the evaporator P1.

Based on such a principle, the present invention appropriately controls at least one of the amount of heat supplied to the preheating evaporator 6 and the amount of water supplied from the water supplier 9 to the preheating evaporator 6 shown in FIG. In addition, the temperature of the hydrogen-containing gas introduced into the shift unit 3 is appropriately controlled by appropriately controlling the amount of water stored in the water trap unit 7 of the heat exchange unit 8 in the hydrogen generator 100a.

Next, the basic operation of the hydrogen generator according to Embodiment 1 of the present invention will be described with reference to FIG.

[0077] First, when starting the fuel cell system according to the present invention, the water supply device 9 and the raw material supply device 10 are operated to supply water and the raw material gas to the preheating evaporation unit 6 of the hydrogen generator 100a. To do. Here, in the present embodiment, as a raw material gas, a city gas containing methane after desulfurization as a main component is used. The water supply is set so that it contains oxygen molecules that are three times the amount of carbon atoms in the average composition of the raw material gas. In this embodiment, since the city gas mainly composed of methane is used as the raw material gas, The required amount of water is supplied to the preheating evaporator 6 because 3 mol of water vapor is present per methane. That is, water is supplied from the water supplier 9 toward the preheating evaporator 6 so that the steam carbon ratio (SZC ratio) is 3.

In the present embodiment, the raw material gas and water are supplied from the upper part of the preheating evaporation unit 6. As a result, the raw material gas and water are heated by the high-temperature combustion gas discharged from the heating unit 1 and heat transfer from the selective oxidation unit 4 and the transformation unit 3 inside the preheating evaporation unit 6. Finally, due to the heat transfer through the heat exchange unit 8, the preheating evaporation unit 6 before the reforming unit 2 becomes a mixture of raw material gas and water vapor, and this mixture is supplied to the reforming unit 2. The

In the present embodiment, the air-fuel mixture composed of water vapor and the raw material gas flows from the preheating evaporation unit 6 into the reforming unit 2 with an upward force from the lower side in FIG. Note that the water supplied by the water supply 9 also causes a pressure fluctuation in the preheating evaporation section 6 due to an increase in volume accompanying evaporation. Here, when the pressure fluctuation is large, a fluctuation due to the pressure fluctuation occurs in the supply amount of the raw material gas supplied to the preheating evaporation unit 6 at the same time. However, in the present embodiment, by supplying water from the upper part of the preheating evaporation unit 6 from the water supply unit 9, even when the volume increases due to evaporation, the supplied water follows the gravity and preheats evaporation. Since it can flow downstream in the part 6, it is possible to prevent pressure fluctuations in the preheating evaporation part 6.

In the present embodiment, the water trap portion 7 provided in the heat exchanger 8 is arranged below the preheating evaporator 6 in the direction of the weight. Accordingly, the liquid water discharged from the preheating evaporation unit 6 moves downward in the direction of gravity and is then trapped in the water trap unit 7. For this reason, liquid water is not directly supplied to the reforming catalyst 2a filled in the reforming section 2. Therefore, with such a configuration, it is possible to reliably prevent the reforming catalyst 2a from being destroyed by inhibiting the reforming reaction caused by locally quenching the reforming catalyst 2a.

In the present embodiment, the operation of the heating unit 1 is controlled using the temperature detected by the temperature detection unit 2b as a guide. Here, the high-temperature combustion gas discharged from the heating unit 1 heats the reforming catalyst 2a in the reforming unit 2 and then heats the preheating evaporation unit 6 when passing through the combustion gas channel 5. In the present embodiment, the temperature of the hydrogen-containing gas discharged from the reforming catalyst 2a detected by the temperature detection unit 2b provided immediately after (below) the reforming unit 2 is about 650. The temperature of the combustion gas discharged from the heating unit 1 is controlled so that the temperature becomes ° C. As a result, about 85% of the city gas becomes hydrogen-containing gas by the steam reforming reaction at the outlet of the reforming section 2.

[0082] The direction of travel of the hydrogen-containing gas discharged from the reforming unit 2 is then reversed below the reforming unit 2 and travels upward along the heat exchange unit 8. At this time, the hydrogen-containing gas is supplied to the shift catalyst 3a in the shift section 3 after exchanging heat with the preheating evaporation section 6 side in the heat exchange section 8. Then, in the metamorphic section 3, the concentration of carbon monoxide contained in the hydrogen-containing gas is reduced to a predetermined concentration by a water gas shift reaction using water vapor. Here, in the present embodiment, the transformation unit 3 is operated so that the temperature detected by the temperature detection unit 3b in the transformation unit 3 is about 250 ° C. As a result, the concentration of carbon monoxide contained in the hydrogen-containing gas at the outlet of the shift section 3 becomes about 0.5% (dry gas base). Note that during normal operation, the reaction temperature can be maintained at about 250 ° C by the heat retained in the hydrogen-containing gas discharged from the reforming section 2, so the shift catalyst 3a in the shift section 3 can be used as a heater, etc. There is no need to heat by.

[0083] Thereafter, air is supplied from the selective oxidation air supplier 12 to the hydrogen-containing gas discharged from the shift unit 3. Here, the amount of air supplied to the hydrogen-containing gas from the selective oxidation air supply 12 is set so that the amount of oxygen contained in the hydrogen-containing gas is about twice the number of moles of carbon monoxide and carbon. To do. The amount of air supplied from the selective oxidation air supplier 12 is controlled by setting the amount of air supplied on the basis of the amount of hydrogen to be generated. Further, in the present embodiment, the temperature detected by the temperature detection unit 4b in the selective oxidation unit 4 becomes 125 ° C. by controlling the amount of air supplied from the selective oxidation air supplier 12. Thus, the selective oxidation unit 4 is operated. In addition, an air cooling fan as a selective oxidation cooler is provided in the space between the transformation unit 3 and the selective oxidation unit 4 or the outer wall surface of the selective oxidation unit 4, so that the selective oxidation unit 4 It is good also as a structure which controls operating temperature accurately. In this embodiment, by providing the reforming section 2 below the preheating evaporation section 6 (lower side in the direction of gravity), the mixture gas of raw material gas and water vapor is smoothly transferred from the preheating evaporation section 6 to the reforming section 2. It can be supplied to Even in the case where water cannot be evaporated in the preheating evaporation section 6, the water can be evaporated in the reforming section 2 which becomes high temperature. As a result, it is possible to prevent the steam necessary for the steam reforming reaction to proceed appropriately in the reforming section 2. Stopped.

[0084] Thus, the hydrogen generator 100a according to the embodiment of the present invention operates in the same manner as the operation of a conventional general hydrogen generator during normal operation. Then, through the series of operations described above, the hydrogen generator 100a generates a hydrogen-containing gas so that the concentration of carbon monoxide carbon is about 20 ppm or less.

Next, a characteristic operation of the hydrogen generator according to Embodiment 1 of the present invention will be described with reference to FIG. 1 and FIG.

FIG. 4 is a flowchart schematically showing one cycle of the characteristic operation of the hydrogen generator according to Embodiment 1 of the present invention. Actually, during the power generation operation of the fuel cell system, for example, the operation of one cycle shown in FIG. 4 is continuously executed without being intermittent.

[0087] Now, as shown in FIG. 4, when the generation of the hydrogen-containing gas is started in the hydrogen generator 100a, the controller 14 included in the fuel cell system includes at least one of the temperature detectors 3b and 3c. Based on the output signal, the temperature Ts of the shift catalyst 3a is acquired (step Sl).

Then, the controller 14 determines whether or not the temperature Ts of the shift catalyst 3a is equal to or higher than the upper limit temperature Tu set in advance in the storage unit of the controller 14 (step S2a). Here, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is not higher than the upper limit temperature Tu preset in the storage unit of the controller 14 (NO in step S2a), the shift catalyst 3a It is determined whether or not the temperature Ts is lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (step S2b). Here, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is not lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (NO in step S2b), the controller 14a Acquire temperature Ts again.

On the other hand, when controller 14 determines that temperature Ts of shift catalyst 3a is equal to or higher than upper limit temperature Tu preset in the storage unit of controller 14 (YES in step S2a), controller 14 Increase the amount of water supplied to the preheating evaporator 6 (step S3a). Alternatively, when the controller 14 determines that the temperature Ts of the modified catalyst 3a is equal to or lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (YES in step S2b), the controller 14 preheats from the water supplier 9. Reduce the amount of water supplied to the evaporator 6 (step S3b). Here, in the present embodiment, the water supplier 9 to the preheating evaporator 6 The increase in the amount of water supplied to the is performed according to preset increase data. Similarly, the reduction in the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is also executed according to preset reduction data.

As described above, the characteristic operation of the hydrogen generator 100a according to the present embodiment is that the upper limit temperature Tu and the lower limit temperature T1 are set in advance with respect to the temperature detected by at least one of the temperature detection units 3b and 3c. If the temperature detected by at least one of the temperature detectors 3b and 3c exceeds the upper limit temperature Tu, the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is increased. This is different from the operation of the conventional hydrogen generator in that the amount of latent heat of vaporization is increased in the preheating evaporator 6. In addition, when the temperature detected by at least one of the temperature detection units 3b and 3c is lower than the lower limit temperature T1, the amount of water supplied from the water supply unit 9 to the preheating evaporation unit 6 is reduced to reduce the amount of the preheating evaporation unit. This is different from the operation of the conventional hydrogen generator in that the required latent heat of vaporization in step 6 is reduced.

[0091] Then, the controller 14 determines whether or not the temperature Ts of the shift catalyst 3a is not equal to or higher than the upper limit temperature Tu after the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is increased in step S3a. (Step S4a). Alternatively, the controller 14 determines whether or not the temperature Ts of the shift catalyst 3a does not fall below the lower limit temperature T1 after the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is reduced in step S3b. Is determined (step S4b).

[0092] Here, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is still equal to or higher than the upper limit temperature Tu (NO in step S4a), the water from the water supplier 9 to the preheating evaporator 6 is determined. Further increase the supply amount. Alternatively, if the controller 14 determines that the temperature Ts of the shift catalyst 3a is still below the lower limit temperature T1 (NO in step S4b), the controller 14 reduces the amount of water supplied from the water supplier 9 to the preheating evaporation unit 6. Reduce the dose further.

[0093] On the other hand, when the controller 14 determines that the temperature Ts of the shift catalyst 3a has become lower than the upper limit temperature Tu (YES in step S4a), the controller 14 controls the amount of water supplied from the water supplier 9 to the preheating evaporator 6. While the temperature is maintained, it is determined whether or not the temperature Ts of the shift catalyst 3a is not lower than the lower limit temperature T1 (step S5). Alternatively, when the controller 14 determines that the temperature Ts of the shift catalyst 3a exceeds the lower limit temperature T1 (YES in step S4b), the controller 14 maintains the amount of water supplied from the water supplier 9 to the preheating evaporation unit 6. Whether the temperature Ts of the shift catalyst 3a is equal to or higher than the upper limit temperature Tu is determined. Step S5). Then, the controller 14 causes the temperature Ts of the shift catalyst 3a to decrease excessively and become the lower limit temperature T1 or lower, or the temperature Ts of the shift catalyst 3a increases excessively to reach the upper limit temperature Tu or higher. If (NO in step S5), for example, an alarm is output to the operator or user (step S6). However, when the temperature Ts of the shift catalyst 3a is between the upper limit temperature Tu and the lower limit temperature T1 (YES in step S5), the controller 14 ends the temperature control of the shift catalyst 3a.

[0094] As described above, the characteristic operation of the hydrogen generator 100a according to the present embodiment is that the temperature of the shift catalyst 3a in the shift section 3 is set to an optimum temperature by the operations of steps S1 to S5 shown in FIG. This is different from the operation of the conventional hydrogen generator in terms of control.

[0095] Here, the reason why the temperature Ts of the shift catalyst 3a in the shift section 3 can be reduced is that the amount of water supplied from the water supplier 9 to the preheating evaporation section 6 is increased, thereby increasing the heat exchange section 8 In this way, the amount of water stored in the water trap section 7 is increased, and this increases the amount of heat exchange from the hydrogen-containing gas discharged from the reforming section 2 to the preheating evaporation section 6 side. This is because the temperature of the produced hydrogen-containing gas is lowered. On the other hand, the reason why the temperature Ts of the shift catalyst 3a in the shift section 3 can be increased is that the amount of water supplied from the water supply 9 to the preheating evaporation section 6 is reduced so that heat exchange can be achieved. The amount of water stored in the water trap part 7 in the part 8 is reduced, and this reduces the amount of heat exchange to the preheating steaming part 6 side of the hydrogen-containing gas power discharged from the reforming part 2. This is because the temperature of the hydrogen-containing gas supplied to the tank rises.

[0096] Further, in the hydrogen generator 100a configured by integrating the carbon monoxide removal unit such as the reforming unit 2, the conversion unit 3, and the selective oxidation unit 4, heat transfer is stable at each operating temperature. Therefore, when the temperature of one reaction zone changes, the balance changes, and it may not be possible to maintain the optimum operating temperature. That is, the change in the temperature of the carbon monoxide removal section is often caused by the supply balance of water or source gas being lost. In particular, when the supply amount of water changes, for example, if the supply amount of water becomes lower than the supply amount assumed for some reason, the temperature of the shift catalyst 3a in the shift section 3 increases as described above. Become. Therefore, according to the configuration shown in the present embodiment, the control is performed to increase the amount of water supplied from the water supplier 9 to the preheating evaporator 6, so that the temperature detector 3b (or temperature detector) is finally used. The effect that the temperature detected by part 3c) is stabilized within the proper range and the supply amount of water within the proper range can be supplied is also exhibited. In this embodiment, the temperature of the shift catalyst 3a in the shift section 3 is supplied for the steam reforming reaction by providing the heat exchange section 8 in the flow path of the hydrogen-containing gas to the shift section 3. It can be easily controlled by controlling the amount of water supplied.

Further, in the present embodiment, it is necessary to determine the upper limit temperature Tu and the lower limit temperature T1 set in advance in the storage unit of the controller 14 in consideration of the catalyst characteristics of the shift catalyst 3a.

FIG. 6 is a graph schematically showing the results of one evaluation example regarding the temperature activity of the Cu—Zn-based shift catalyst according to Embodiment 1 of the present invention. FIG. 6 shows the result of an evaluation example in a stationary phase flow device for a Cu—Zn-based shift catalyst. Further, in FIG. 6, a pseudo mixed gas obtained by adding water vapor to a hydrogen balance gas (dry gas base) having a carbon monoxide content of 10% and a carbon dioxide content of 10% is used. Assuming steam reforming reaction S / C = 2.7, S / C = 3.0, S / C = 3.3 Space velocity (SV) = 1 .

[0099] According to FIG. 6, in order to effectively reduce the concentration of oxy-carbon in the hydrogen-containing gas discharged from the reforming section 2 related to the value of SZC, It is desirable to control the temperature of the shift catalyst 3a to about 220 ° C.

[0100] On the other hand, according to FIG. 6, it can be seen that as the value of SZC decreases, the reduction efficiency of carbon monoxide decreases particularly in the low temperature region. In an actual hydrogen generator, the temperature of the shift catalyst 3a in the shift section 3 rises as the amount of water supplied from the water feeder 9 to the preheating evaporation section 6 decreases, so that the monoacid contained in the hydrogen-containing gas It is unlikely that the carbon concentration will rise significantly. In this state, when the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is increased, the temperature of the shift catalyst 3a in the shift section 3 decreases, but the S / C value increases. Therefore, there is little possibility that the reduction efficiency of carbon monoxide and carbon will be remarkably lowered. For this reason, it is possible to control so that the concentration of carbon monoxide contained in the hydrogen-containing gas discharged from the shift section 3 does not increase.

[0101] In the present embodiment, for example, the upper limit temperature Tu is set to 240 ° C and the lower limit temperature T1 is set to 200 ° C with respect to the temperature detected by the temperature detection unit 3b. And water supply 9 Force By appropriately increasing or decreasing the amount of water supplied to the preheating vaporization section 6, the concentration of carbon monoxide contained in the hydrogen-containing gas at the outlet of the transformation section 3 exceeds 0.5% (dry gas base). Control to not. The upper limit temperature Tu and the lower limit temperature T1 with respect to the temperature detected by the temperature detector 3b are the configuration of the hydrogen generator 100a, such as the size of the shift catalyst 3a, the type of catalyst to be applied, the amount of catalyst charged, and the operating conditions. Is different. Therefore, in setting the upper limit temperature Tu and the lower limit temperature T1, it is necessary to measure and determine in advance the correlation between the amount of water supplied and the temperature detected by the temperature detector 3b for each hydrogen generator 100a. In the present embodiment, the temperature of the shift catalyst 3a in the shift section 3 is detected by the temperature detector 3b or the like disposed in the vicinity thereof. However, the shift section 3 is not limited to this configuration. As long as the temperature of the shift catalyst 3a can be detected directly or indirectly, the temperature detector can be arranged at any position.

[0102] In the present embodiment, for example, a water flow meter is disposed between the water supply unit 9 and the preheating evaporation unit 6, and the upper limit supply amount of water supplied to the preheating evaporation unit 6 is set. And the lower limit supply amount are set respectively, it becomes possible to detect the performance deterioration of the temperature detectors 3b and 3c in the fuel cell system. That is, the self-diagnosis of the fuel cell system can be performed.

[0103] For example, a water flow meter is built in the water supply device 9, and an upper limit supply amount and a lower limit supply amount are provided in advance with respect to the supply amount of water supplied from the water supply device 9 to the preheating evaporator 6. For example, when the temperature detected by the temperature detector 3b is equal to or higher than the upper limit temperature Tu and the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is increased, the increased amount of water If the supply amount is greater than or equal to the upper limit supply amount described above, it is determined that performance degradation has occurred in the temperature detectors 3b and 3c and the like. Alternatively, when the temperature detected by the temperature detection unit 3b is lower than the lower limit temperature T1, and the amount of water supplied from the water supply unit 9 to the preheating evaporation unit 6 is reduced, the supply of water after the reduction is made When the amount is equal to or less than the above-described lower limit supply amount, it is determined that the performance deterioration has occurred in the temperature detection units 3b and 3c.

[0104] Further, another example will be described. In this embodiment, the hydrogen generator 100a in which the reforming unit 2, the reforming unit 3, and the selective acid tank unit 4 illustrated in this embodiment are integrated. In this case, when the supply amount of the raw material gas and water is stable, heat transfer is stable at each operating temperature. Therefore, the temperature of each reaction part changes in a relatively stable state. Therefore, by controlling the amount of water supplied from the water supplier 9, the temperature of the shift catalyst 3a in the shift section 3 can be stabilized within the assumed range.

For example, if the temperature detected by the temperature detection unit 3b is not controlled within the assumed range even if the amount of water supply is controlled within the assumed range, Heat exchange is unstable. In this case, it is considered that the amount of water supplied from the water supplier 9 to the preheating evaporator 6 deviates from the expected range as a factor that causes instability in the transfer of heat. For example, when the performance of the water supply device 9 deteriorates over time, water may not be supplied with the correct supply amount with respect to the input voltage. In addition, even if the performance of the temperature detector such as the temperature detector 3b deteriorates over time, it may not be stable within the initially assumed temperature range. In such a case, if the operation of the fuel cell system is continued without taking any special measures, if the amount of water actually supplied is small, the hydrogen-containing gas discharged from the shift section 3 will be reduced. Concentration of contained carbon monoxide increases. In addition, when the amount of water that is actually supplied is large, excessive heat energy is consumed to evaporate the water, resulting in a decrease in hydrogen generation efficiency. However, according to the configuration in which the flow meter described above is installed and the upper limit supply amount and the lower limit supply amount are set for the water supply amount, the performance of the water supply unit 9 and the temperature detection units 3b and 3c, etc. Since the deterioration can be detected, the characteristic operation of the hydrogen generator 100a exemplified in the present embodiment can be suitably and reliably executed. In addition, according to the configuration, it is possible to avoid the continuation of abnormal power generation operation of the fuel cell system.

[0106] As described above, in the hydrogen generator in which the reforming unit, the shift unit, and the selective oxidation unit are integrated, the size is increased when a separate temperature control mechanism is provided for each reaction unit in order to optimize the individual operating temperature. According to the present embodiment, the amount of water supplied to the preheating evaporation unit is changed to change without reducing the hydrogen generation efficiency. The temperature of the shift catalyst 3a in part 3 can be controlled appropriately.

[Embodiment 2]

Hardware configuration of a hydrogen generator according to Embodiment 2 of the present invention and driving the same The configuration of additional hardware for performing this operation and the basic operation of the hydrogen generator are the same as in the first embodiment. Accordingly, in the second embodiment of the present invention, those descriptions are omitted.

[0108] The difference between the characteristic operation of the hydrogen generator shown in the present embodiment and the characteristic operation of the hydrogen generator shown in Embodiment 1 is, for example, the temperature detected by the temperature detector 3b. The upper limit temperature Tu and the lower limit temperature T1 are set in advance, and the amount of combustion air supplied to the heating section 1 when the temperature detected by the temperature detection section 3b exceeds the upper limit temperature Tu Is to reduce the weight. Another difference is that, for example, when the temperature detected by the temperature detection unit 3b is lower than the lower limit temperature T1, the supply amount of combustion air supplied to the heating unit 1 is increased. . Such a characteristic operation makes it possible to control the temperature of the shift catalyst 3a in the shift section 3 to an optimum temperature.

Hereinafter, a characteristic operation of the hydrogen generator according to Embodiment 2 of the present invention will be described with reference to FIG. 1 and FIG.

FIG. 5 is a flowchart schematically showing one cycle of the characteristic operation of the hydrogen generator according to Embodiment 2 of the present invention.

Now, as shown in FIG. 5, when the generation of the hydrogen-containing gas is started in the hydrogen generator 100a, the controller 14 included in the fuel cell system has at least one of the temperature detectors 3b and 3c. Based on the output signal, the temperature Ts of the shift catalyst 3a is acquired (step Sl).

[0112] Then, the controller 14 determines whether or not the temperature Ts of the shift catalyst 3a is equal to or higher than the upper limit temperature Tu set in advance in the storage unit of the controller 14 (step S2a). Here, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is not higher than the upper limit temperature Tu preset in the storage unit of the controller 14 (NO in step S2a), the shift catalyst 3a It is determined whether or not the temperature Ts is lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (step S2b). Here, when it is determined that the temperature Ts of the shift catalyst 3a is not lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (NO in step S2b), the temperature Ts of the shift catalyst 3a is acquired again.

[0113] On the other hand, if the controller 14 determines that the temperature Ts of the shift catalyst 3a is equal to or higher than the upper limit temperature Tu preset in the storage unit of the controller 14 (YES in step S2a), the combustion air The amount of air supplied from the feeder 11 to the heating unit 1 is reduced (step S3a). Alternatively, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is equal to or lower than the lower limit temperature T1 preset in the storage unit of the controller 14 (YES in step S2b), from the combustion air supply 11 Increase the amount of air supplied to heating unit 1 (step S3b). Here, in the present embodiment, the reduction in the amount of air supplied from the combustion air supply 11 to the heating unit 1 is executed in accordance with preset reduction data. Similarly, the increase in the amount of air supplied from the combustion air supply 11 to the heating unit 1 is executed according to preset increase data.

[0114] As described above, the characteristic operation of the hydrogen generator 100a according to the present embodiment is that the upper limit temperature Tu and the lower limit temperature T1 are set in advance with respect to the temperature detected by at least one of the temperature detection units 3b and 3c. If the temperature detected by at least one of the temperature detection units 3b and 3c exceeds the upper limit temperature Tu, the amount of air supplied from the combustion air supply 11 to the heating unit 1 is reduced. This is different from the operation of the conventional hydrogen generator in that the amount of heat supplied to the preheating evaporator 6 is reduced. In addition, when the temperature detected by at least one of the temperature detection units 3b and 3c is lower than the lower limit temperature T1, the amount of air supplied from the combustion air supply unit 11 to the heating unit 1 is increased. This is different from the operation of the conventional hydrogen generator in that the amount of heat supplied to the preheating evaporator 6 is increased.

[0115] Then, after the amount of air supplied from the combustion air supply 11 to the heating unit 1 is reduced in step S3a, the controller 14 reduces the temperature Ts of the shift catalyst 3a below the upper limit temperature Tu. It is determined whether or not (step S4a). Alternatively, the controller 14 determines whether or not the temperature Ts of the shift catalyst 3a exceeds the lower limit temperature T1 after the amount of air supplied from the combustion air supply 11 to the heating unit 1 is increased in step S3b. Is determined (step S4b).

[0116] Here, when the controller 14 determines that the temperature Ts of the shift catalyst 3a is still equal to or higher than the upper limit temperature Tu (NO in step S4a), the controller 14 sends the combustion air supply 11 to the heating unit 1. Reduce the air supply further. Alternatively, if the controller 14 determines that the temperature Ts of the shift catalyst 3a is still below the lower limit temperature T1 (NO in step S4b), the controller 14 supplies air from the combustion air supply 11 to the heating unit 1. Increase supply further.

[0117] On the other hand, if the controller 14 determines that the temperature Ts of the shift catalyst 3a is less than the upper limit temperature Tu (YES in step S4a), the air from the combustion air supply 11 to the heating unit 1 Supply While maintaining the amount, it is determined whether or not the temperature Ts of the shift catalyst 3a is lower than the lower limit temperature T1 (step S5). Alternatively, when the controller 14 determines that the temperature Ts of the shift catalyst 3a exceeds the lower limit temperature T1 (YES in step S4b), the controller 14 maintains the air supply amount from the combustion air supply 11 to the heating unit 1. Whether or not the temperature Ts of the shift catalyst 3a is equal to or higher than the upper limit temperature Tu is determined (step S5). Then, the controller 14 detects when the temperature Ts of the shift catalyst 3a is excessively decreased to the lower limit temperature T1 or lower, or when the temperature Ts of the shift catalyst 3a is excessively increased to be higher than the upper limit temperature Tu ( In step S5, NO), an alarm is output to the operator or user (step S6). However, when the temperature Ts of the shift catalyst 3a reaches a temperature between the upper limit temperature Tu and the lower limit temperature T1 (YES in step S5), the controller 14 ends the temperature control of the shift catalyst 3a.

[0118] As described above, the characteristic operation of the hydrogen generator 100a according to the present embodiment is that the temperature of the shift catalyst 3a in the shift section 3 is set to an optimum temperature by the operations of steps S1 to S5 shown in FIG. This is different from the operation of the conventional hydrogen generator in terms of control.

[0119] Here, the reason why the temperature Ts of the shift catalyst 3a in the shift section 3 can be lowered will be described as follows.

[0120] That is, by reducing the amount of air supplied from the combustion air supply 11 to the heating unit 1, the flow rate of the combustion gas supplied to the combustion gas channel 5 is reduced. The amount of heat supplied to the preheating evaporator 6 is reduced. At this time, since the necessary amount of latent heat of vaporization required in the preheating evaporation unit 6 is constant, the amount of water stored in the water trap unit 7 in the heat exchange unit 8 is increased. As a result, the amount of heat exchanged to the preheating vaporization section 6 side of the hydrogen-containing gas power discharged from the reforming section 2 is increased, so that the temperature of the hydrogen-containing gas supplied to the shift section 3 is lowered. Therefore, the temperature Ts of the shift catalyst 3a in the shift section 3 can be lowered.

[0121] The reason why the temperature Ts of the shift catalyst 3a in the shift section 3 can be raised is explained as follows.

[0122] That is, by increasing the amount of air supplied from the combustion air supply 11 to the heating unit 1, the flow rate of the combustion gas supplied to the combustion gas channel 5 is increased. The amount of heat supplied to the preheating evaporator 6 is increased. At this time, since the required amount of latent heat of vaporization required in the preheating evaporation unit 6 is constant, the amount of water stored in the water trap unit 7 in the heat exchange unit 8 Is reduced. As a result, the amount of heat exchanged to the preheating evaporation section 6 side of the hydrogen-containing gas power discharged from the reforming section 2 is reduced, so that the temperature of the hydrogen-containing gas supplied to the shift section 3 rises. Therefore, the temperature Ts of the shift catalyst 3a in the shift section 3 can be increased.

[0123] In this embodiment, the relationship between the voltage applied to the sirocco fan or the like and the supply amount of air is created in a database in advance, thereby increasing or decreasing the supply amount of air supplied to the heating unit 1 Control is performed by changing the voltage applied to a fan or the like. In addition, by creating a database of the relationship between the rotation speed of the sirocco fan and the supply amount of air, it is possible to increase or decrease the supply amount of air supplied to the heating unit 1 even by controlling the rotation speed of the sirocco fan. It is.

[0124] For example, the upper limit temperature Tu and the lower limit temperature T1 set with respect to the temperature detected by the temperature detection unit 3b are the size of the shift catalyst 3a, the type of catalyst to be applied, the amount of catalyst loaded, the operation It differs depending on the configuration of the hydrogen generator 100a, such as the conversion conditions. Therefore, in setting the upper limit temperature Tu and the lower limit temperature T1, it is necessary to measure and determine in advance the correlation between the supply air amount and the temperature detected by the temperature detection unit 3b for each hydrogen generator 100a.

Also in the present embodiment, for example, an air flow meter is disposed between the combustion air supply 11 and the heating unit 1, and the upper limit for the amount of air supplied to the heating unit 1 is set. By setting the supply amount and the lower limit supply amount, it is possible to detect the performance deterioration of the temperature detectors 3b and 3c in the fuel cell system. That is, the self-diagnosis of the fuel cell system can be performed.

[0126] For example, an air flow meter is built in the combustion air supply unit 11, and the upper limit supply amount and the lower limit supply are supplied in advance to the supply amount of air supplied from the combustion air supply unit 11 to the heating unit 1. Provide an amount. Then, when the temperature detected by the temperature detection unit 3b is equal to or higher than the upper limit temperature Tu and the amount of air supplied from the combustion air supply 11 to the heating unit 1 is reduced, the amount of air after the reduction is reduced. When the supply amount is equal to or less than the above-mentioned lower limit supply amount, it is determined that the performance deterioration has occurred in the temperature detectors 3b and 3c. Alternatively, when the temperature detected by the temperature detection unit 3b becomes the lower limit temperature T1 or less and the supply amount of air supplied from the combustion air supply unit 11 to the heating unit 1 is increased, the air after the increase is increased. The supply amount is as described above. If it exceeds the limit supply amount, it is judged that the performance has deteriorated in the temperature detectors 3b and 3c.

[0127] Further, another example will be described. In this embodiment, the hydrogen generator 100a in which the reforming unit 2, the reforming unit 3, and the selective acid tank unit 4 illustrated in this embodiment are integrated. In this case, when the supply amount of the raw material gas and water is stable, the transfer of heat is stable at each operating temperature, and therefore the temperature of each reaction section changes in a relatively stable state. . Therefore, by controlling the amount of air supplied from the combustion air supply 11, the temperature of the shift catalyst 3 a in the shift section 3 can be stabilized within an assumed range.

For example, if the temperature detected by the temperature detection unit 3b is not controlled within the assumed range even if the air supply amount is controlled within the assumed range, the heat in each reaction unit is controlled. The delivery of is unstable. As a factor that causes instability in the transfer of heat, the supply amount of air supplied from the combustion air supply 11 to the heating unit 1 may deviate from the expected range.

[0129] For example, when the performance of the sirocco fan disposed in the combustion air supply device 11 has deteriorated over time, air may not be supplied with a correct supply amount with respect to the input voltage. In addition, even when the performance of the temperature detection unit such as the temperature detection unit 3b deteriorates over time, it may not be stable within the initially assumed temperature range. Furthermore, there may be a case where the white fan cannot sufficiently exhibit a predetermined capacity due to blockage of an air intake port in the combustion air supply 11 or an increase in pressure loss inside the heating unit 1.

[0130] In such a case, if the operation of the fuel cell system is continued without taking any special measures, the combustion gas discharged from the heating unit 1 is reduced if the amount of air actually supplied is small. The concentration of carbon monoxide contained increases. On the other hand, when the supply amount of air actually supplied is large, the combustion state in the heating unit 1 becomes unstable, and again the concentration of carbon monoxide contained in the combustion gas discharged from the heating unit 1 Rises. Alternatively, since the heat energy taken out of the combustion gas discharged from the hydrogen generator 100a increases, the hydrogen generation efficiency in the hydrogen generator 100a decreases.

[0131] However, according to the configuration in which the above-described flowmeter is provided and the upper limit supply amount and the lower limit supply amount are set as the air supply amount, the combustion air supply 11 and the temperature detection units 3b and 3 Since performance degradation such as c can be detected, the characteristic operation of the hydrogen generation apparatus 100a exemplified in this embodiment can be suitably and reliably executed. Further, according to such a configuration, it is possible to avoid the continuation of abnormal power generation operation of the fuel cell system.

[0132] As described above, in the hydrogen generation apparatus in which the reforming section, the conversion section, and the selective oxidation section are integrated, the size is increased when a separate temperature control mechanism is provided for each reaction section in order to optimize the individual operating temperature. According to the present embodiment, by changing the supply amount of air supplied to the heating unit, the transformation unit that does not reduce the hydrogen generation efficiency. The temperature of the shift catalyst 3a in 3 can be appropriately controlled.

[0133] The other points are the same as in the first embodiment.

[Embodiment 3]

The hardware configuration of the hydrogen generator according to Embodiment 3 of the present invention, the configuration of additional hardware for driving the same, and the basic operation of the hydrogen generator are described in the embodiment. Same as 1 and 2. Therefore, in the third embodiment of the present invention, description thereof is omitted.

[0135] The characteristic operation of the hydrogen generator 100a shown in the present embodiment is the characteristic operation of the hydrogen generator 100a shown in the first embodiment and the characteristic operation of the hydrogen generator 100a shown in the second embodiment. The operation will be described as an appropriate combination of various operations.

That is, for example, the upper limit temperature Tu and the lower limit temperature T1 are set in advance for the temperature detected by the temperature detection unit 3b, and the supply amount of water supplied from the water supplier 9 to the preheating evaporation unit 6 is set. However, the upper limit supply amount and the lower limit supply amount are set in advance. When the temperature detected by the temperature detection unit 3b is equal to or higher than the upper limit temperature Tu and the supply amount of water supplied from the water supply unit 9 to the preheating evaporation unit 6 is equal to or higher than the upper limit supply amount, the heating unit 1 Reduce the amount of combustion air supplied to. Also, for example, when the temperature detected by the temperature detection unit 3b is lower than the lower limit temperature T1 and the supply amount of water supplied from the water supply unit 9 to the preheating evaporation unit 6 is lower than the lower limit supply amount, the heating unit Increase the amount of combustion air supplied to 1. By such a characteristic operation, the temperature of the shift catalyst 3a in the shift section 3 is adjusted to an optimum temperature. Control appropriately at every degree.

[0137] Here, in order to effectively reduce the concentration of carbon monoxide contained in the hydrogen-containing gas in the shift section 3, a certain amount of water supplied from the water supplier 9 to the preheating evaporator 6 is secured. It is desirable to do. On the other hand, in order to sufficiently secure the hydrogen generation efficiency in the hydrogen generator 100a, it is necessary to avoid a significant increase in the amount of water supplied from the water supplier 9 to the preheating evaporator 6.

[0138] According to the present embodiment, the first control factor that increases or decreases the amount of water supplied from the water supplier 9 to the preheating evaporator 6 and the amount of water supplied from the combustion air supplier 11 to the heater 1 are as follows. Since the temperature of the shift catalyst 3a in the shift section 3 is controlled by two control factors, the second control factor that increases or decreases the air supply amount, the difference between the upper limit supply amount and the lower limit supply amount related to the water supply amount is controlled. (That is, it is possible to suppress the change width of the water supply amount). In addition, since it becomes possible to suppress the difference between the upper limit supply amount and the lower limit supply amount, the temperature of the reforming catalyst 2a and the selective oxidation catalyst 4a in the reforming unit 2 other than the shift unit 3 and the selective oxidation unit 4 can be reduced. Can be stabilized.

[0139] When the change amount of the amount of water supplied from the water supplier 9 to the preheating evaporator 6 is set small, the force that reduces the temperature control range of the shift catalyst 3a in the shift portion 3 exceeds the control range. Even in this case, the temperature of the shift catalyst 3a in the shift section 3 can be controlled by controlling the amount of air supplied from the combustion air supply 11 to the heating section 1. As a result, it is possible to suppress the generation probability of carbon monoxide and carbon in the metamorphic section 3, and to control the operating temperature of the carbon monoxide removing section to a more appropriate operating temperature.

[0140] Further, in addition to the control operation described above, by combining the control for adjusting the combustion amount in the heating unit 1 so that the temperature detected by the temperature detection unit 2b becomes a preset temperature, the heating unit Even when the amount of combustion air supplied to 1 is increased, the operating temperature in the reforming unit 2 is stabilized and the hydrogen generation reaction is also stabilized, so that the hydrogen generator 100a is operated more appropriately. be able to.

[0141] Further, for example, the upper limit temperature Tu and the lower limit temperature T1 set for the temperature detected by the temperature detection unit 3b are the size of the shift catalyst 3a, the type of catalyst to be applied, the amount of catalyst loaded, the operation It differs depending on the configuration of the hydrogen generator 100a, such as the conversion conditions. Therefore, upper limit temperature In setting the temperature Tu and the lower limit temperature Tl, the correlation between the amount of water supplied to the preheating evaporator 6 and the amount of air supplied to the heating unit 1 and the temperature detected by the temperature detector 3b is previously determined for each hydrogen generator 100a. It needs to be determined by measurement.

[0142] The other points are the same as in the first and second embodiments.

[Embodiment 4]

The hardware configuration of the hydrogen generator according to Embodiment 4 of the present invention, the configuration of additional hardware for driving the same, and the basic operation of the hydrogen generator are described in the embodiment. It is the same as the case of 1-3. Therefore, in Embodiment 4 of the present invention, description thereof is omitted.

[0144] The characteristic operation of the hydrogen generator 100a shown in the present embodiment is the characteristic operation of the hydrogen generator 100a shown in the first embodiment and the characteristic operation of the hydrogen generator 100a shown in the second embodiment. The operation will be described as other operations appropriately combined with other operations.

That is, for example, the upper limit temperature Tu and the lower limit temperature T1 are set in advance with respect to the temperature detected by the temperature detection unit 3b, and the amount of air supplied from the combustion air supply 11 to the heating unit 1 is set. In contrast, an upper limit supply amount and a lower limit supply amount are set in advance. Then, when the temperature detected by the temperature detection unit 3b is equal to or higher than the upper limit temperature Tu and the supply amount of air supplied from the combustion air supply 11 to the heating unit 1 is equal to or lower than the lower limit supply amount, the water supply 9 From there, increase the amount of water supplied to the preheating evaporator 6. Also, for example, when the temperature detected by the temperature detection unit 3b is lower than the lower limit temperature T1 and the supply amount of air supplied from the combustion air supply 11 to the heating unit 1 is higher than the upper limit supply amount, Reduce the amount of water supplied from the feeder 9 to the preheating evaporator 6. With such a characteristic operation, the temperature of the shift catalyst 3a in the shift section 3 is appropriately controlled to an optimum temperature.

[0146] The difference between the characteristic operation of the hydrogen generator 100a shown in the present embodiment and the characteristic operation of the hydrogen generator 100a shown in the third embodiment is that the combustion air supply 11 This is because the setting of the upper limit supply amount and the lower limit supply amount with respect to the supply amount of air supplied to 1 is prioritized. As a result, when the air supply amount is low, which is a problem related to the operation of the heating unit 1, the concentration of carbon monoxide contained in the combustion gas increases, or when the air supply amount is large, combustion occurs. The concentration of carbon monoxide and carbon contained in the gas increases, and the combustion gas Problems such as an increase in the thermal energy that is taken out from the hydrogen generator 100a can be preferentially avoided.

Here, when the difference between the upper limit supply amount and the lower limit supply amount with respect to the supply amount of air supplied from the combustion air supply device 11 to the heating unit 1 is large, the supply amount of air supplied to the heating unit 1 is Otherwise, incomplete combustion occurs and the concentration of carbon monoxide contained in the combustion gas increases. Further, if the amount of air supplied to the heating unit 1 is large, the combustion state becomes unstable, and the concentration of carbon monoxide contained in the combustion gas increases. Alternatively, since the thermal energy that the combustion gas brings out of the hydrogen generator 1 OOa increases, the hydrogen generation efficiency of the hydrogen generator 100a decreases.

[0148] According to the present embodiment, the first control factor that increases or decreases the amount of water supplied from the water supplier 9 to the preheating evaporator 6 and the amount of water supplied from the combustion air supplier 11 to the heater 1 are as follows. Since the temperature of the shift catalyst 3a in the shift section 3 is controlled by two control factors, the second control factor that increases or decreases the air supply amount, the difference between the upper limit supply amount and the lower limit supply amount related to the air supply amount It is possible to suppress (that is, the change width of the air supply amount). Further, since the difference between the upper limit supply amount and the lower limit supply amount can be suppressed, the temperature of the reforming catalyst 2a in the reforming section 2 can be stabilized. In addition, it becomes possible to sufficiently ensure the temperature controllability of the shift catalyst 3a in the shift section 3.

[0149] When the change width of the air supply amount from the combustion air supply 11 to the heating unit 1 is set small, the control range of the temperature of the shift catalyst 3a in the shift unit 3 is narrowed. Even when the control range is exceeded, the temperature of the shift catalyst 3a in the shift section 3 can be controlled by controlling the amount of water supplied from the water supply unit 9 to the preheating evaporation section 6. . As a result, the generation probability of carbon monoxide and carbon in the metamorphic section 3 can be suppressed, and the operating temperature of the carbon monoxide removing section can be controlled to a more appropriate operating temperature.

[0150] The other points are the same as in the first to third embodiments.

[0151] As described above, in the hydrogen generator according to the embodiment of the present invention, the upper limit temperature and the lower limit temperature are set in advance with respect to the temperature detected by the temperature detection unit for detecting the temperature of the shift unit. When the temperature detected by the temperature detector exceeds the upper limit temperature, the amount of water supplied from the water feeder to the preheating evaporator is increased, so that the preheating evaporator Increase the amount of latent heat of vaporization. As a result, the amount of heat exchange from the hydrogen-containing gas discharged from the reforming section to the preheating evaporation section increases, so the temperature of the hydrogen-containing gas supplied to the shift section decreases, and the temperature of the shift catalyst in the shift section Can be reduced. On the other hand, when the temperature detected by the temperature detection unit is below the lower limit temperature, the amount of water supplied from the water supply to the preheating evaporation unit is reduced, so that the required latent heat of vaporization is obtained in the preheating evaporation unit. Reduce the amount. As a result, the amount of heat exchange from the hydrogen-containing gas discharged from the reforming section to the preheating evaporation section decreases, so the temperature of the hydrogen-containing gas supplied to the shift section rises, and the shift catalyst in the shift section increases. The temperature can be raised. These control operations make it possible to appropriately control the temperature of the shift catalyst in the shift section.

[0152] Further, according to the hydrogen generator according to the embodiment of the present invention, the upper limit supply amount and the lower limit supply amount are set in advance for the supply amount of water supplied from the water supplier to the preheating evaporator, and the temperature detection is performed. When the temperature detected at the outlet is equal to or higher than the upper limit temperature and the water supply force is also higher than the upper limit supply rate, or the temperature detected by the temperature detector is lower than the lower limit. It can be determined that the operation of the hydrogen generator is abnormal when the temperature is below the temperature and the amount of water supplied from the water supplier to the preheating evaporator is below the lower limit. Here, in a hydrogen generator that integrates a carbon monoxide removal unit such as a reforming unit, a shift unit, and a selective oxidation unit, the amount of heat exchange in the preheating evaporation unit is determined by the amount of water supplied, so each reaction The temperature balance of the part is generally constant. Therefore, by setting the upper limit temperature and the lower limit temperature for the temperature detected by the temperature detection unit within a range that does not hinder the operation of the hydrogen generator, the amount of water supplied to the preheating evaporation unit is reduced. It can be judged whether it is within the assumed range, and an abnormality outside the assumed range in the hydrogen generator can be judged.

[0153] In addition, when the upper limit temperature and the lower limit temperature are set in advance with respect to the temperature detected by the temperature detection unit and the temperature detected by the temperature detection unit exceeds the upper limit temperature, the fuel supplied to the heating unit is set. By reducing the amount of air supplied for baking, the amount of heat generated by the heating unit to the preheating evaporation unit provided outside the heating unit can be reduced. In this case, since the necessary amount of latent heat of vaporization required in the preheating evaporation unit is constant, the amount of heat exchange from the hydrogen-containing gas discharged from the reforming unit to the preheating evaporation unit increases and is supplied to the transformation unit. The temperature of the hydrogen-containing gas is low I will give you. Thereby, the temperature of the shift catalyst in the shift section can be lowered. In addition, when the temperature detected by the temperature detection unit falls below the lower limit temperature, the amount of combustion air supplied to the heating unit is increased to the preheating evaporation unit provided outside the heating unit. The amount of heat of the heating part can be increased. In this case, since the necessary amount of latent heat of vaporization required in the preheating evaporation unit is constant, the amount of heat exchange from the hydrogen-containing gas discharged from the reforming unit to the preheating evaporation unit is reduced and supplied to the transformation unit. The temperature of the hydrogen-containing gas increases. Thereby, the temperature of the shift catalyst in the shift section can be increased.

[0154] Further, by providing an upper limit supply amount and a lower limit supply amount in advance with respect to the supply amount of air supplied from the combustion air supply to the heating unit, the temperature detected by the temperature detection unit becomes equal to or higher than the upper limit temperature. In addition, if the supply amount of air supplied to the heating unit falls below the lower limit supply amount, or the temperature detected by the temperature detection unit falls below the lower limit temperature, the combustion air supply force is heated from the combustion air supply unit. It can be determined that the operation of the hydrogen generator is abnormal when the supply amount of air supplied to the section exceeds the upper limit supply amount. Here, in a hydrogen generator that integrates a carbon monoxide removal unit such as a reforming unit, a transformation unit, and a selective oxidation unit, the supply amount of water and raw materials to be supplied is stable! Since the heat exchange amount in each part is determined, the temperature balance in each reaction part is almost constant. Therefore, by setting the upper limit temperature and the lower limit temperature for the temperature detected by the temperature detector within a range that does not hinder the operation of the hydrogen generator, the operation of the combustion air supply device is within the expected range. Therefore, it is possible to determine an abnormality outside the assumed range in the hydrogen generator.

[0155] In addition, an upper limit supply amount and a lower limit supply amount are provided in advance for the amount of water supplied to the water supply power preheating evaporation unit, and the temperature detected by the temperature detection unit exceeds the upper limit temperature and the water supply If the amount of water supplied to the preheating evaporator from the heater exceeds the upper limit supply, the amount of combustion air supplied from the combustion air supply to the heating unit is reduced. Alternatively, when the temperature detected by the temperature detection unit is lower than the lower limit temperature and the supply amount of water supplied from the water supply unit to the preheating evaporation unit is lower than the lower limit supply amount, the combustion air supply unit supplies the heating unit. Increase the amount of combustion air supplied to the engine. In order to control the temperature of the shift catalyst in the shift section by these two control factors, the upper limit supply amount and the lower limit supply It is possible to provide a margin for setting the amount. In addition, the probability of carbon monoxide generation in the carbon monoxide removal unit can be reduced, and the operating temperature of the carbon monoxide removal unit can be controlled to a more optimal operation temperature. By using these control operations in combination with adjusting the amount of combustion in the heating section so that the temperature detected by the temperature detection section for detecting the temperature of the reforming catalyst becomes a preset temperature, Since the steam reforming reaction in the reforming section can be stabilized, the hydrogen generator can be operated more optimally.

[0156] In addition, an upper limit supply amount and a lower limit supply amount are set in advance for the supply amount of air supplied from the combustion air supply to the heating unit, and the temperature detected by the temperature detection unit exceeds the upper limit temperature and combustion When the supply amount of air supplied from the air supply unit to the heating unit falls below the lower limit supply amount, the supply amount of water supplied from the water supply unit to the preheating evaporation unit is increased. Or, if the temperature detected by the temperature detector is lower than the lower limit temperature and the supply amount of air supplied to the combustion air supply power heating unit is higher than the upper limit supply amount, the water supply unit supplies the preheating vaporizer. Reduce the amount of water supplied to. Since the temperature of the shift catalyst in the shift section is controlled by two powerful control factors, it is possible to provide a margin for setting the upper limit supply amount and the lower limit supply amount. In addition, the generation probability of carbon monoxide and carbon in the monoxide and carbon removal section can be reduced, and the operating temperature of the carbon monoxide removal section can be controlled to a more optimal operation temperature.

[0157] Further, by supplying the upward force material and water in the gravity direction in the preheating evaporation section, it becomes possible to suppress the pressure fluctuation that occurs when water evaporates in the preheating evaporation section. Water can be supplied smoothly.

[0158] When the carbon monoxide removal unit is a shift unit, a temperature detection unit is provided in the shift unit to detect the temperature of the shift catalyst, thereby stabilizing the temperature state of the shift catalyst in the shift unit. Therefore, it is possible to supply the fuel cell with a high-quality hydrogen-containing gas in which the concentration of carbon monoxide is sufficiently reduced without increasing the amount of air supplied to the selective oxidation unit.

[0159] According to the present invention, with a relatively simple structure, the carbon monoxide such as a reforming section, a shift section, and a selective oxidation section that generates a hydrogen-containing gas by a steam reforming reaction between a raw material gas and water. In a hydrogen generator in which the element removal section is arranged in a cylindrical shape around the heating section and integrated, the temperature of the shift catalyst in the shift section can be appropriately controlled without providing a special temperature control mechanism. become. In addition, since a temperature control mechanism such as an air cooling fan is not required, it is possible to configure a hydrogen generator that does not increase the amount of heat released. In addition, it is possible to realize both the simplicity of the configuration of the hydrogen generator without compromising the hydrogen generation efficiency required for the hydrogen generator and the enhancement of the hydrogen generation efficiency.

Industrial applicability

[0160] In the hydrogen generator according to the present invention, liquid water having the power of the preheat evaporator is trapped by the water trap unit, so that liquid water is directly supplied to the reforming catalyst filled in the reformer, and reforming is performed. The catalyst can be used industrially as a hydrogen generator capable of stable hydrogen generation, because the possibility of inhibiting the reforming reaction and destroying the catalyst caused by local rapid cooling of the catalyst is reduced. The

[0161] Further, in the fuel cell system including the hydrogen generator according to the present invention, the hydrogen generator is stably operated, and a high-quality hydrogen-containing gas having a stable composition is stably supplied to the fuel cell. It can be used industrially as a fuel cell system capable of stable power generation operation.

Claims

The scope of the claims

[1] A heater that burns an air-fuel mixture of combustion fuel and combustion air to generate combustion gas, and the raw material and water are heated by the combustion gas generated by the heater so that the raw material and water vapor are heated. An annular preheat evaporator that produces a mixture with

An annular reformer that generates a hydrogen-containing gas by passing the air-fuel mixture generated by the preheat evaporator through a reforming catalyst heated by the combustion gas, below the preheat evaporator;

With

A hydrogen generator, further comprising a water trap section for trapping the liquid water from which the preheat evaporator power is also discharged.

[2] The annular reformer is further provided on the outer periphery of the preheat evaporator, and further includes an annular shifter incorporating a shift catalyst for reducing carbon monoxide in the hydrogen-containing gas generated by the reformer by a shift reaction. 2. The hydrogen generator according to claim 1, wherein the hydrogen-containing gas supplied from a mass device to the transformer and the liquid water in the water trap section are configured to exchange heat.

[3] Outside the heater, the preheating evaporator, the water trap unit, the reformer and the transformer are each provided in a cylindrical shape,

The transformer is provided around the preheating evaporator,

The preheating evaporator, the water trap part, and the reformer are connected in series so that the air-fuel mixture is supplied from the preheating evaporator to the reformer through the water trap part,

3. The hydrogen generation apparatus according to claim 2, wherein the hydrogen-containing gas generated in the reformer is configured to come into contact with the water trap unit before being supplied to the transformer.

4. The hydrogen generator according to claim 3, wherein the raw material supply port and the water supply port are provided on the other end side where the water trap portion of the preheating evaporator is not connected.

[5] a combustion air supply for supplying the combustion air to the heater;

A water supply for supplying the water to the preheating evaporator;

A temperature detector for detecting the temperature of the shift catalyst incorporated in the shift converter, and a controller,

Based on the temperature of the shift catalyst detected by the temperature detector, the controller 3. The hydrogen generator according to claim 2, wherein at least one of a water supply amount from the water supply device to the preheat evaporator and a combustion air supply amount from the combustion air supply device to the heating device is controlled.

[6] A storage device having information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst is provided,

The controller controls the water supply unit to increase the amount of water supplied to the preheating evaporator when the temperature detected by the temperature detector exceeds the upper limit temperature. 6. The hydrogen generator according to claim 5, wherein when the detected temperature is equal to or lower than the lower limit temperature, the water supply device is controlled so as to reduce the amount of water supplied to the preheating evaporator.

[7] The storage device further includes information on an upper limit supply amount and a lower limit supply amount relating to the control of the water supply amount,

When the controller supplies the water supply amount from the water supply unit to the preheating evaporator equal to or higher than the upper limit supply amount, or the water supply amount from the water supply unit to the preheating evaporator is equal to or less than the lower limit supply amount. 7. The hydrogen generator according to claim 6, wherein an abnormality is determined when it becomes.

[8] A storage device having information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst,

The controller controls the combustion air supply device to reduce the amount of combustion air supplied to the heater when the temperature detected by the temperature detector is equal to or higher than the upper limit temperature, and the temperature 6. The hydrogen generator according to claim 5, wherein when the detected temperature of the detector becomes equal to or lower than the lower limit temperature, the combustion air supply device is controlled to increase the supply amount of combustion air to the heater.

[9] The storage device further includes information on an upper limit supply amount and a lower limit supply amount related to the control of the combustion air supply amount,

When the controller supplies the combustion air supply amount from the combustion air supply device to the heater equal to or higher than the upper limit supply amount, or the combustion air supply amount from the combustion air supply device to the heater 9. The hydrogen generation apparatus according to claim 8, wherein an abnormality is determined when the value becomes equal to or less than the lower limit supply amount.

[10] A storage device having information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst and information on an upper limit supply amount and a lower limit supply amount related to control of the water supply amount,

When the temperature of the shift catalyst becomes equal to or higher than the upper limit temperature and the water supply capacity of the preheat evaporator becomes equal to or higher than the upper limit supply quantity, the controller supplies the heater to the heater. Controlling the combustion air supply unit to reduce the combustion air supply amount, the temperature of the shift catalyst is equal to or lower than the lower limit temperature, and the water supply amount from the water supply unit to the preheating evaporator is the lower limit supply. 6. The hydrogen generator according to claim 5, wherein the combustion air supply device is controlled to increase the amount of combustion air supplied to the heater when the amount becomes less than the amount.

[11] A storage device including information on an upper limit temperature and a lower limit temperature related to temperature control of the shift catalyst and information on an upper limit supply amount and a lower limit supply amount related to the control of the combustion air supply amount. When the temperature of the shift catalyst becomes equal to or higher than the upper limit temperature and the amount of combustion air supplied from the combustion air supply to the heater becomes equal to or lower than the lower limit supply, water to the preheating evaporator is Controlling the water supply unit to increase the supply amount, wherein the temperature of the shift catalyst is not more than the lower limit temperature, and the combustion air supply amount from the combustion air supply unit to the heater is not less than the upper limit supply amount 6. The hydrogen generator according to claim 5, wherein the water supply device is controlled so as to reduce the amount of water supplied to the preheating evaporator when the value becomes.

[12] The hydrogen generator according to claims 1 to 11,

A fuel cell that generates electricity using the hydrogen-containing gas and the oxygen-containing gas supplied from the hydrogen generator;

A fuel cell system comprising at least a fuel cell system.